Electrical switching and connecting apparatus



Aug. 20, 1940. w. H. LINDAE ELECTRICAL SWITCHING AND CONNECTING APPARATUS 3 Sheets-Sheet 1 Z'/v VENTOE W/W/nm /1. Lin due.

Aug. 20, 1940. w. H. LINDAE 3 3 ELECTRICAL SWITCHING AND CONNECTING APPARATUS Filed Dec. 24, 1936 s Sheets -Sheet 2 W WM INVENTOE F 010. H Lina a6.

1 9 I jayc w Aug. 20, 1940. w. H. LINDAE ELECTRICAL SWITCHING AND CONNECTING APPARATUS Filed Dec. 24, 1956 3 Sheets-Sheet 3 IN I/E/V TOE WWW/67m /7 A [ma a6.

TTOE/VEY Patented Aug. 20, 1940 UNITED STATES PATENT [OFFICE ELECTRICAL SWITCHING AND CONNECTING v 1 APPARATUS William H. Lindae, St. Louis, Mo.

Application December 24, 1936, Serial No. 117,603

6 Claims. (01. 2001 66) This invention relates generally to electrical shown in opened position, that is, disengaged switching and connecting apparatus and, more from the contact-post: particularly, to a new and useful improvement in Figure 4 is a'fragmentary side elevational view contacts for cooperativeembodiment in' apparaof a disconnecting switch of my invention havtus of the type mentioned. j ing a base adapted for connection to a plurality 5 It is known that contact resistance is a function of bus-bars or feeder lines; of pressure and not of area, and that by decreas- Figure 5 is a fragmentary side elevational view ing the contact area to a point or a line and inof an electrical disconnecting switch of my increasing the pressure, greater contact efliciency vention having another form of base adapted for w is obtained. Nevertheless, high contact presconnection to a plurality of bus-bars or feeder sures produce diificulty in switch operation. lines; 7 Moreover, the limited contact surface which ac- Figure 6 is anend elevational view of an elec-' companies point contact area necessarily octrical connector clamp embodying my present incasions relatively high temperature at the point vention;

of contact, which must, of course, be dissipated Figure 7 is a side elevational view of the con- 15 through the metal-work of the switch structure. nector clamp of Figure 6;

' My present invention, hence, has for its Figures 8, 9, and 10, respectively, illustrate'a primary object the provision in electrical switchseries of fragmentary sectional views of various ing and connecting apparatus of point contacts modified contacts for providing low resistance of unique formation presenting low resistance contact areas'in accordance with my present inwithsuperiorcurrent-carrying characteristics. vention; r I r a My invention has also for an object the-pro- Figures 11 and 12 are, respectively, enlarged vision, in electrical switching and connecting fragmentary side elevational views of contact apparatus of the type stated, of means for the post constructions embodying my present invenconnection of the switch elements to the bus or tion; and v V 5' line uniquely constructed not only for the Figures 13, 14, and 15 are, respectively, front, elimination of preliminary preparations for the side, and end elevational views of a bus-bar cable prevention of a high resistance therebetween, but connector embodying my present invention. also'for facile clampwise connection for obtain- Referring now in more detail and by reference ing ample and adequate current-carrying characters-to the drawings, which illustrate capacity with minimum resistance. losses. practical embodiments of my invention, A, in

My invention has for a further object to gen Figures 1 designates a disconnecting erally "improve upon, and reduce the cost of Switch of the typefmo-re particularly described manufacture, installation, and maintenance of, and disclosed in my co-pending application,

electrical switching and connecting apparatus of Serial No. 71,665, filed March 30, 1936, of which 35 the type stated. this present application is a continuation in part,

' And with the above and other objects in view, the switch A including a-pair of spaced insulator my invention resides in the novel features of stands or supports I, 2, common in such con-j form,-construction, arrangement, and cQmbinastructions and well known to those skilled in 40 tion of parts presently described and pointed out the'art- H I I in the claims. Disposed rigidly upon corresponding faces of In the accompanying drawings (three sheets): the ql Stands 2, r electricallyton'? Figure 7 [is a t plan view of a single pole ductive base or terminal plates'3, 4, upon which 1 single throw disconnecting switch embodying one the operating parts of the switch A are mounted;-

form 'of my invention, the insulation supports as described in my said co-pending applicati and bus bars or line terminal connections being e c of the P131768 b ng provided with a shown by dot-dash lines; preferably integral laterally projecting connec- "Figure 2 is a side elevational view, partly lion-area: extension b aving an aperture 5 for broken away and in section, of the switch of e v a s a e-connection-bolt 6.

50, Figure 1; Disposed in each extension b around its aper- 0 Figure 3 is an enlarged frag y ide'eleture 5, "is" a series of contact-plugs 1, inthe vational View of the latch end of the swingable present instance three in number, of relatively blade and its associated stationary contact post small diameter or area and formed of suitable of the switch of Figure 1, other parts of the highly conductive material whose sulphideis also 5,structure bein O t d and the ade being preferably conductive, such as silver or the like.

The plugs I are welded or otherwise attached to, or inset into, one or both faces of the extension b to project outwardly therefrom a small, but yet appreciable, distance, so that, when the particular bus-bars, as, for instance, bars W, are mounted on the terminal plates 3, i, the plugs I will be compressed therebetween for establishing a substantially small contact area under heavy pressure and, at the same time, providing a small free or ventilating space between the relatively opposite faces of the bus-bar W and the particular terminal plate, thus providing a unique type of electrical joint construction having the characteristics of high current-carrying capacity with low resistance losses and high heat-dissipation efficiency.

In contrast to the usual and, so far as I am aware, heretofore necessary, laborious Work and painstaking care required to insure perfectly flat contact surfaces between the conducting members to be connected, it will be seen that, inmy construction, a highly eiificient electrical joint connection may, with the greatest of ease and facility and with minimum expenditure of time and labor, be readily formed in the field during the installation of the switch or other structure.

The switch A also includes a plurality of transverse connection blades 8 and connector posts 9, as more fully described and disclosed in my said copending application, each of the blades 8 being formed upon its inner face with an arcuate depression or channel I0 extending upwardly or inwardly from the leading edge II thereof. Rigidly disposed or fixed in and at the base of the channel I0, is a contact-plug I2 formed in similar manner to the contact plugs I and arranged for contacting engagement with a spherical or ball-like end I3 of the contact post 9, which end I3 may, in turn, be formed integrally with the post 9 or may be provided with an inserted contact member of a type and in a manner presently fully described.

The switch illustrated in Figure 4 is especially designed for connection with a plurality of busbars or feeder lines, and accordingly the base or terminal member is in the form, as shown, of a suitably elongated or oblong-rectangular conducting block b longitudinally slotted or furcated for a portion of its length and thereby preferably integrally provided with a series of suitably spaced parallel superposed tongues I5, the spaces between the respective tongues I5 providing channels I6 for accommodating respective bus-bars W and the several tongues I5 being provided with pairs of perpendicularly aligned apertures I'I, I8, for receiving suitable fastening elements in the form preferably of bolts I9, 20. Disposed in the contact faces of each of the tongues I5 around their respective apertures l1, I8, is a plurality of contact-plugs 2| of a character and type similar to the contact plugs I previously described and likewise formed of a suitable conductive material, such as silver or the like. The plugs 2|, further, are similarly welded or otherwise attached to the tongues I5 and project outwardly therefrom a small, but yet appreciable, distance, so that, when the particular bus-bars W are inserted into the channels I 6 and the bolts I9, 20, tightened down, the plugs 2I will co-operatively form both securing and electrical connection with the bus-bars W in the same manner as that previously described in connection with the contact plugs I and the bus-bars W. Preferably plates 50 are disposed and fixed in the channels I6 adjacent the base thereof, as

shown, for strengthening the block b, ventilating or air spaces, as at 5|, however, being preferably provided at the base of the channels I6.

In electrically connecting the switch A with an electrical conductor of the multi-strand or cable type, the base or terminal b" of the switch A is preferably integrally formed with a connector block B provided with a plurality of perpendicularly extending apertures 22 forreceiving suitable attaching elements, such asbolts 23, and the upper and lower contact faces 24, 25, of the block B being, in turn, provided with a plurality of 'V-shaped transverse channels or notches 2B.

Flatwise disposed upon the contact faces 24, 25, respectively, of the block B, is a pair of platesections 2'! having complementary V-shaped channels or notches 28 and being also provided with a plurality of complementary apertures 29, the channels or notches 28 and the apertures 29 being, respectively, disposed for alignment with the channels or notches 26 and the apertures, 22 of the block B, as best seen in Figure 5.

Disposed in, and extending perpendicularly outwardly from, the base wall of each of the channels 26, 28, is a plurality of plugs 30 of relatively small diameter or area and formed in a similar manner and of like materal to that previously described in connection with theinsert or plugs I and 2|. It will be evident that, when the stripped ends of electrical cables C are inserted or laid in the channels and the bolts 23 tightened to bring the engagement plates 21 down tightly thereupon, the plugs 39 will bite into the cables C and be compressed to form a high pressure small area contact therewith, thus establishing not only a firm, secure union between the parts, but also an electrical joint of a highcurrent-carrying capacity with low resistance losses and excellent heat-dissipation efficiency.

Similarly, the present invention may be incorporated in a connector plate or bracketsuitable for mounting on instrument panels and the like. Accordingly, D designates a connector bracket comprising, as shown in Figures 6 and 7, a base or terminal member b' provided with a preferably integrally formed and somewhat enlarged lateral extension 33 having apertures 34 for accommodating suitable attaching members, such as screws or the like, not shown, for conveniently securing the base member b to a panel or other support. The base member 11" is also provided,

with a longitudinally extending, V-shaped-channel 35 and a pair of transverse internally threaded apertures 36 for receiving the threaded shanks of suitable attaching members, such as socket-headed bolts or the like 31. Adapted for disposition upon the upper face ofthe body-extension 32, is a top or engagement plate 38 ha ving a complementary longitudinally extending; V-shaped channel 39 and being, also provided.

with a pair of complementary aperturessfifli for alignment with the channel 35 and the apertures 36 in the terminal member extension33.

Disposed in, and projecting perpendicularly upwardly from, the base wall of the channels 35 and.

Disposed in the under face of the extension 33 of the terminal member 12", is a plurality of contact-plugs 42 formed in a similar manner and of like material to that describedin connection with the contact plugs 'I and 2I.

,The silver or other such inserts I; 2|, 30, 41;

and 42 may take various forms, more especially in the respect that such plugs may be provided on both sides, for instance, of the switch blades 8 in the switch A, or the tongues I5 in themultir terminal base plate I), as at i in Figure 8; again, instead of the plug form of insert, a silver rivet having flattened heads, as at I in Figure 9, or silver discs, as at 1 in Figure 10,may be provided, as may best serve the purpose, all such several forms of silver contact-surfaces permitting the mere reversal of the bar for restoring the efliciency of the contact surface when the same is impaired by wear.

Further, in accordance with the present invention, I may provide variously constructed silver insert members in co-operation with the contact-post 9. Thus, a silver ring 43 may be incorporated in the spherical or ball-like head L3 of the post 9 in Figure 11, or a plurality of segmental plug members 44 may be welded or otherwise attached to the face of the spherical or ball-like head 53 in Figure 12. The heads 93* and 3 may also be formedseparately from the post 9, and post 9 centrally apertured toaccommodate attachment means, such as a round-headed screw 45 extending through the particular head and threadedly engaging in the post 9. Furthermore, the post 9 at its upper end may be provided with a frustro-conical upstanding shoulder 9* for press-fit engagement with a complementarily shaped recess in the ball 13 as best seen in Figure 11. Thus, the heads I3 or l3 may be readily removed and replaced in efficient electrical contact with thepost without the necessity of dismantling the entire switch or connector device.

I may still further provide a clamp type connector for connecting a cable to a bus-bar, which, as shown in Figures 13, 14, and 15, comprises a pair of A-shaped body members 46 shiftably held in parallel clamp-wise juxtaposition by bolts 41 and having a plurality of opposed contact inserts 48 mounted uponrthe respective inner faces thereof for engagement with the bus-bar :L. Preferably integrally formed with one of the members 46 is a cable socket 49 having a cylindrical recess and also having a plurality of contact inserts 5| disposed upon its inner face. Extending threadedly through the side wall of the socket into the recess 50 is a set screw 52 for retainingly forcing the cable 11 into engagement with the contact members 5|.

It will be understood that changes and modifications in the form, construction, arrangement, and combination of the several parts of the structure may be made and substituted for those herein shown and described without departing from .the nature and principle of my invention.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

1. In an electrical device, an upstanding connector post having a threaded recess extending axially inwardly from an end thereof, an annular contact member mounted on the end of the post, and a headed screw extending through the contact member and threadedly engaged in the post recess, the outer surface of the screw head and the annular member being arcuately end member upon said post. p

2. In an electrical device, an upstanding connector post having althreaded recess extending axially inwardly from an end thereof, an annular contact member, mounted on the end of the post, and a headed screw extending through the contact member and threadedly engaged in the post recess, the outer surface of the screw'head the-annular member being'arcuately con"-v toured to form a substantially ball-shaped end member upon said post,,said annular contact member being provided in its outer face with aplurality of outwardly extending contact buttons formed of. a low-resistance metal.

3! In an electrical device, an upstanding connector post having an upwardly extending frusto-conical tongue provided with a threaded recess extending axially inwardly from an end thereof, an annular contact member mounted on the frusto-conical member, and a headed screw extending through the contact member and threadedly engaged in the post recess, the

contoured to form a substantially ball-shaped outer surface of the screw head and the annular being provided in its outer facewith an annular I silver band.

5. In an electrical device, an upstanding connector post having a recess opening to its upper end, an annular contact member disposed on said post, and a headed securing member extending through the contact member and engaged'in the'post recess, the outer surface ofthe contact member and of the head of the securing} member being arcuately contoured to form a substantially ball-shaped end member upon said post.

6. In an electrical device, an upstanding connector post having a recess opening to its upper end, an annular contact member disposed on said post, and a headed securing member extending through the contact member and engaging in the post recess, the outer surface of the contact member and of the head of the securing member being arcuately contoured to form a substantially ball-shaped end member uponsaid post, said annular contact member being further provided in its outer face with a plurality of outwardly extending contact buttons formed of a low-resistance metal. 

